Mechanical footwear testing machine



A. A. AlNEs 2,638,776 MECHANICAL FOOTWEAR TESTING MACHINE 2 Sheets-Sheetl May 19, 1953 Filed Aug. l, 1947 J du: 2 2 g la r ,//Id

im@ *qu May 19, 1953 A. A. AINEs MECHANICAL FOOTWEAR TESTING MACHINE 2Sheets-Sheet 2 Filed Aug. 1, 1947 ull 3 O32 3 33 2 Ma INVEN TOR.

wdm, Arron/wey Patented May 19, 1953 UNITED MECHANICAL FOOTWEAR TESTINGMACHI Andrew A. Aines, United States Army, Petersburg, Va.

Application August 1, 1947, Serial No. 765,619

6 Claims. (Cl. i3-7) (Granted under Title 35, U. S. Code (1952),

sec. 266) ratus and especially to a machine for testing the lWearabilityand durability of shoes.

A primary object of the invention consists in the provision of a testingmachine provided with feet on which shoes may be placed and the machineoperated so as to simulate actual conditions `of use, as when Walking.

A further object of the invention 'resides lin the incorporation in themachine of heating means and perspiration simulating means so thatactual service conditions may be reproduced and varied as desired.

A still further object of the invention consists in providing a machineWhich is capable of sub- 4jecting shoes to actual Wearing` conditions ata A high rate of speed so as to indicate, in a matter of hours, theamount of wear which Would be produced in shoes over a period of Weeksor months of actual use.

Another object of the invention resides in the provision of means forheating or cooling 'the track with which the shoes cooperate.

Other objects and advantages of the invention will be apparent from thefollowing description ,taken in connection with the accompanyingdrawings, in which, f i

Figure l is a front elevational View of the apparatus with the rear huband related parts removed.

Figure Z is a plan View of the apparatus with one of the shafts brokenaway.

Figure 3 is an enlarged sectional view through one of the artificiallegs and related parts.

Figure 4 is a front elevational View of one of the artificial legs, and

4Figures 5, 6 and 7 are detail views of one of the shock-absorbingelements.

In the testing of shoes it is essential that the shoes being tested besubjected to the same wear and tear to which shoes are subjected inactual use, and to this end it is necessary that the shoes being testedbe applied to a surface with pressure corresponding to that which wouldbe applied by the wearer and that the shoes be moved relatively to thesurface in a manner `corresponding to the movement of the feet of aperson when Walking or running. But it is immaterial Whether the surfacebe moved relatively to the shoe supporting wheel or vice versa. In thepresent illustration,

the mechanism is intended for outdoor operation `mounted on and radiatefrom the hubs. `are preferably formed of live resilient rubber surandthe surface is xed While the testing apparatus is considered to be movedbodily about the surface which is in the form of an annular track ofapproximately 50 feet in diameter. l

The numeral indicates a base preferably formed of concrete and to whichis applied the annular track or surface 2. This tread-surface ortrackway may be suitably roughened in simulation of conventionalpavements or the like and to this end may be coated with abrasive garnetor carborundum imbedded in the concrete surface to provide an optimumindex of resistance to the shoes as they are applied to and removed fromthe tread-surface. Also, one or more pipes 2 may be embedded in theconcrete, slightly below the surface thereof, through Which heating orcooling mediums may pass so as to approximate varying Weatherconditions. Disposed centrally of the trackway 2 is a pedestal or thelike 3 on the upper end of which is rotatably mounted a disc i. Thisdisc may be rotated at the desired speed by any preferred means, but inthe present instance an electric motor t operating through a gearreduction box 6 and sprocket chain l provides the necessary motivepower. Extending radially from the disc are a plurality of equallyspaced horizontal rods t, of which four are employed in the presentembodiment of the invention. Each of these rods 8 is providedintermediate its end with a shock-absorbing element Vwhich is shown indetail in Figures 5, G and 7 and comprises a casing 9 Xed to the outerend of the rod and forming a housing for a pair of compression springsl0. The outer side of the housing is provided with a verticallyextending slot Il through which extends a rod I2. This rod is providedon its inner end with a piston i3 having pins It on its upper and lowerends which are received within the coils of the compression springs lo.Rotatably mounted on the outer ends of the rods i2 are the hubs l5 onwhich the artificial leg-foot members are mounted. It will thus beapparent that the shock-absorbing element, through the medium of thesprings lil and slot Il serves to avoid damage to the apparatus in theevent that any obstruction should be encountered by the shoes beingtested.

ln the present illustration, eight of the artificial leg-foot membersare attached to each of the hubs l5 and consequently these hubs are ofoctagonal form so that the artificial legs may be suitably The legsrounding a centrally arranged metal tubular area.'

aeeavve member. As clearly indicated in Figure 3 a metal tubular section2d is threaded or otherwise xedly secured to each of the eight nattenedsurfaces of the hub i5 and surrounding and xed to each tubular section2@ is a section 2l of live resilient rubber which is .representative ofthe upper portion of each leg. Fixed to the lower end of the tube 2t isa rectangular plate 22. The lower portieri of the leg is also formed ofa central tubular section 23 of metal surrounded by aliveresilientrubber section 2li and to the upper endof` the tube 23 is fixed arectangular metal plate 25. The plates 22 and 25 are loosely connectedagainst separation by means of bolts 2t which are threaded into theplate 25. By suitably adjusting these bolts the alignment of theelements 2l and 2limay be varied so as to alter the angle of gait.Interposed between these plates is a compression spring 2l which acts toprovide the necessary pressure of the shoe on the track '2, and normallymaintains `the leg sections 2i and 2d in their adjustedy relationship.

'I'hearticial foot is lindicated by numeral 28 and is also preferablyformed of live resilient rubber. This foot member is xed to a verticalplate 29 pivotally connected at its upper end within the lowerend of thetubular section 23 as indicated by numeral 3d, and the tubeis slotted asindicated luy-.numeral 33 to permit the plate to move about its pivot.Slightly below the pivot point 30 the plate 29;;is provided withy ahorizontal slot 3l through `.which extends a pin 33 fixed adjacent thelower .end .of the tubular member v2t to provideqthe lnecessary,articulation between the foot an'd;;leg,. in other words, simulatingthe function of the human ankle. The space between the top of` thefootmember 23 and the bottom of the leg member 2d maybe nlled by a spongerubber section 33 which serves to mask the joint between the foot andleg. The shoes to be tested are indicated by the-letter A and it will beunderstood that. the feet 23 are alternately shaped for right and leftshoes.

-To provide an adequate test of the shoes it is essential that actualconditions be reproduced as accurately as possible and to this end meansare provided vfor heating the feet which are to be incased by the shoes,and preferably socks, and also means for simulating naturalperspiration. For thispurpose any type of electric heater 49 may besuitably mounted 'within the interior of the foot 28-so as to extendover and parallel the plantar To provide the simulated perspiration eachfoot has imbedded-in its outer surface a plurality-of wicks-1liextending laterally from Va-main wick portion 42. Terminating Vat oradjacent to wick-portion@ isa lexible tube'll which has its upper end incommunication with the-interior of astank. 44 .fixed to the outersurface of each of thehubslEi.. These tanks, oi course, aresuppliedwvith liquid preferably having a chemical formula approximating.that of natural perspiration andthis liquid will. be fed through thetubes llitothewicks il by centrifugal force during the rotation of thehubs i5 as the latter are rotated intheir travel along the track 2.

In the operation of the device, the shoes to be tested, right and left,are applied to the feet 28, preferably after socks have been appliedthereto. The. tanks 44 are provided with the proper liquid, thebolts 26adjusted to provide the desired angularrelationship between the legmembers 2l and 24, and the current turned on the heaters 49. The motor 5is then set in operation to cause the disc!!v to rotate and `thereby'bodily move the hubs I5 about the trackway 2. In this movement 0l.' thehubs I5 about the track `the various shoes A mounted on the legs of eachhub are caused to be successively brought into contact with the track;the heels of the shoe rst engaging the track as in normal walkingandthenthe sole, after which the shoe leaves the track as the heel ofthe suoceeding shoe is brought into contact with the track. The desiredpressure of the shoe against v.the track, corresponding to the weight ofa person, is imparted by the springs 2l. During these operations theinterior of the shoe is heated, as in natural walking or running, bymeans of the heater 4S and the moisture or perspiration is supplied fromthe tank 44 by means of the tubes i3 discharging the liquid on to thewicks 4I and 122.

From Vthe foregoing description and the attached drawings it will beapparent to those skilled in the art that I have devised anapparatusicrtesting shoes which is of rather simple construction; thatit is capable of subjecting shoes to wear and tear in a mannercloselyresembling the conditions to which shoes are subjected inordinary use; and that the apparatus may roperate at high speed so as toapply to the shoes, in a matter of hours, stresses and strainscorresponding inamount yto those normally met with over a period ofseveral months or more.

In accordance with the patent statutes I have describedwhat I nowconsider to be the preferred embodiment of the invention but variouschanges mayobviously be made in the details of construction without inany way ydeparting from the spirit of the invention, and itisintendedthat all such changes be ,includedwithin `the'zscope of the in.-tended claims.

I claim:

1. Footwear testing apparatus. comprising an artificial foot adapted toreceive a shoe, a circular track, pipes disposed beneath lthe track for-conveying .a `heating or cooling medium therebeneath, and'nieans tooperate the foot to bring the shoe into contact with the track inasimulated walking movement.1

ZnFootwear testingl apparatus comprising a circular track, a vrotatablymounted horizontally disposed disc spaced above the track, a hubrotatably connected to the disc radially thereof, a plurality ofarticial feet radiating from the vhub and adaptedl to extend to oradjacent the track, a shock-absorbing element mounted between thehub'anddisc permitting up and down movement of the hub, and means forrotating the disc.

3. In a footwear testing apparatus, an articial foot, a plurality ofwick-like members extending about the footya source of artificialperspiration, and means for conveying the artificial perspiration-*to`said wicks.

4. In a footwear testing apparatus, an articial leg and foot, said legcomposed of upper and lower spaced-apart sections, bolt-receiving meanssecured to the adjacent ends of said sections, a

compressionspring interposed between the adjacent ends.v of vsaidsections, and bolts positioned in the bolt-receiving means for adjustingthe angular relation. between said sections.

5. In a footwear testing apparatus, an artificial leg and foot, said legcomposed of upper and lower spaced-apart sections, plates. secured `tothe adjacent .ends ofsaid sections, a compression spring interposedbetween the plates, and means interconnecting said plates foradjustingthe angular relation of saidplates.

ANDREW A. AINES.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date Stubbs Dec. 23, 1919 Erb Dec. 13, 1921 Coffin Aug. 9, 1927Harrington Sept. l2, 1944 Carter Mar. 4, 1947 OTHER REFERENCES Anarticle entitled, Mechanical walker test shoe soles, found on page 29 ofPopular Science Monthly, Jan. 1936.

